Fiber-tip pen



A ORNE 2 1: m r 1v M. T 2 .6 5 m w d E I G. '2

Hiroyuki Matsumoto HIROYUKI MATSUMOTO v FIBER-T PEN Filed Aug! 1965 Apr 1968 wdx United States Patent Office 3,377,124 FIBER-TIP PEN Hiroyuki Matsumoto, Tokyo, Japan, assignor to Dai Nihon Bungu Co., Ltd. Filed Aug. 31, 1965, Ser. No. 483,994

1 Claim. (Cl. 401-198) 1 ABSTRACT OF THE DISCLOSURE A marking pen having a fiber core extending from a marking end into an ink reservoir. A valve means located peripherally to the core is opened by axial pressure on the marking end of the core. When open, ink has an unobstructed flow path from the reservoir, through the valve means and onto the lateral surfaces of the marking end of the absorbent fiber core.

The present invention relates to a fiber or marking pen of the type which uses a fiber point for dispensing the ink.

There are presently many fiber or marking pens in use. These pens have the disadvantage that no provision is made to keep the fiber point moist with ink While the pen is not in use. This causes difiiculty in getting the pens to initially write and the pen will either blot or skip so that one is not guaranteed smooth, even writing each and every time the pen is put to use. The problem of skipping is especially apparent when inks having a high pigment content, such as white inks, are used. As they do not easily flow from the ink reservoir to the pen point, the use of highly pigmented inks presents a further problem of pigment blocking of the fiber point since the pigment tends to become hard upon drying and cannot be easily redissolved.

The present invention has as its object the provision of a fiber ink pen which overcomes these disadvantages even when a highly pigmented ink is used.

In accordance with the present invention, a fiber or marking pen is provided comprising a container or liquid reservoir for the ink, a fiber writing core immersed in the ink, and a cap structure having a spring loaded valve attached to the core which valve opens upon the exertion of writing pressure on the fiber core to allow ink to flow from the container down the surfaces of the core to the point. The provision of the fiber core extending down into the ink supply allows the ink to be drawn up to the writing point of the fiber core by capillary action to keep the fiber core moist during non-use and thereby prevent ink blocking of the core. The provision of a valve which opens upon the application of writing pressure to the point allows the ink, especially heavy inks, to flow toward the point to supply the point with the necessary ink for writing, thereby overcoming the difficulties in attempting to cause a heavy ink to flow through the fiber core.

The invention will be described with more particularity in connection with the drawings in which:

FIGURE 1 is a cross-sectional view of one embodiment of the present invention; and

FIGURE 2 is a cross-sectional view of another embodiment of the present invention.

In the drawings, a container for an ink supply 1 is provided having threads on the outer surface of the neck for securing the pen assembly to the container. The container may be made of any suitable material such as metal, glass, or plastic as desired. Inserted into the neck of the container 1 is a spring retainer cup 2 having an outwardly extending lip which contacts the upper edge of the mouth to prevent the cup from falling into the interior of the container. The spring retainer cup 2 is further provided with an opening 3 for the passage of the fiber writ- 3,377,124 Patented Apr. 9, 1968 ing core 6 therethrough. The opening 3 is slightly larger than necessary for the passage of the core 6 therethrough to allow the ink in the container to pass beyond the spring retainer cup 2 although any orifice in the spring retainer to allow ink passage may be used. A spring retainer surface 4 is provided around the opening 3.

. The writing core 6 is provided with a writing surface on one end thereof, the other end extending down into the container for contact with the ink supply. The core may be made of any suitable material such as felt held together by a resinous material. The main requirement for the core is that it be fairly stifl. and resistant to breakage while retaining the porosity necessary for ink fiow. The core may be of any desired shape, round being preferred.

Attached to the core 6 is a valve member 7 having a beveled upper sealing surface and a lower spring retaining surface. A valve seat means 9 in the form a cap for the container is secured to the container 1 by thread receiving grooves 10 on the inner surface of the cap. The cap is formed to include a beveled valve seat surface 11, an inner lip 12 for sealingly engaging the cap with the spring retaining cup 2, andan opening 13 in the upper end of the cap for the writing core. A spring 8 positioned between the spring retaining cup 2 and the spring retaining surface of the valve member 7 forces the valve member into sealing engagement with the valve seat 11 of cap 9.

Core opening 13 in cap 9 is made slightly larger than necessary for the passage of the core 6 therethrough to allow ink from the container to flow over the surface of the core when writing pressure applied to the core causes the valve 7 to be opened.

All of the foregoing apparatus parts with the exception of core 6 can be made of any suitable material such as metal, plastic, or glass, or combinations thereof as desired.

FIGURE 2 presents a modification of the basic structure in which a large quantity of absorbent material is positioned around the core near the writing tip to further assist in maintaining the core in a moist condition during non-use.

A thin walled metal container 14 has an ink writing device secured thereto between notch 15 and inwardly bent lip 16. The writing device comprises a spring retaining cup 17 of a character similar to that described hereinabove. Threadedly secured to the upper end of cup 17 is a valve seat means 18 which has a flat valve seat surrounding the opening for the fiber core 21. A valve member 19 is secured to fiber core 21 by means of edge 22 provided by reducing the size of the core at the point where the valve member 19 is to be secured.

A spring 20 positioned between the cup 17 and valve member 19 forces the valve member into sealing engagement with the valve seat means 18. Positioned above the 'valve seat means 18 is a cap 24 provided with an annular compartment for an ink absorbent material 23. The ink absorbent material 23 may be of any absorbent material, felt being preferred. The cap is provided with a chamber 25 which includes a small circumferential space between the inner surface of the cap and the absorbent material to allow the ink to contact the outer surfaces of the absorbent material during use of the pen to keep the absorbent material saturated with ink. Since the absorbent material 23 is in direct contact with the core 21 near the writing tip, the absorbent material assists in maintaining the core in a moist condition.

The pens of the present invention when not in use are kept in a writing condition by capillary action which draws the ink from the container to the writing point to thereby maintain the writing point in a moist condition. The use of the valve assembly allows the ink to flow over the surface of the writing point so that a heavier, highly pigmented ink may be used in place of regular inks.

In addition to the above-described embodiments of the present invention, many other embodiments may be made without departing from the spirit and scope of the invention as defined in the claim hereinafter, and it is to be understood that the invention is not to be limited to the specific embodiments disclosed.

I claim:

1. A fiber-marking pen comprising:

an axially elongated ink container having an upper neck-orifice, a central wick assembly section and a lower ink holding section; a wick assembly-unit axially centrally insertable Within said assembly section, said wick assembly-unit having a lower sector insertable Within said container and an upper sector partially protruding through said neck-orifice; said wick assembly-unit having a wick extending close to the bottom of said lower ink-holding section; said neck orifice comprising an upper inwardly bent annular container-lip and an inwardly protruding circumferential flange spaced parallel to and below said lip; a cup with a central axis orifice and an outwardly bent cup-lip, the diameter of said cup-lip fitting closely with the inner circumference of said neckorifice between said container-lip and said flange; the depth of said cup extending only through said central section of said container; at flat valve seat having a central axial orifice and fitting above said cup-lip within said neck between said container-lip and said flange; said valve seat having on its underside a cylindrical projection for removable connection with the upper portion of said cup; a valve member having an upper flat valve portion with a central axial orifice fitting against the bottom of said valve seat and having a cylindrical lower extension; a coiled compression spring having a central orifice and bearing with its top against the lower side of said valve member and with its bottom against the bottom of said cup; a cylindrical cap having a central axial orifice, having at its bottom an outwardly extending lip, mating in assembly with said container lip and having an inner circumferential chamber adjacent said valve seat; said cylindrical cap provided with an annular compartment; ink absorbent material located within said annular compartment; said material having a central orifice; said wick having a top with a writing surface and lower and an upper section, said upper section having a diameter larger than that of said lower section, the upper section of said wick extending from said top into said assembly adjacent to the upper surface of said valve member; the said central orifices of said cap and of said ink absorbent material fitting said upper portion of said wick, the central orifice of said upper section of said valve seat being slightly larger than the diametcr of said upper portion of the said Wick; the central orifices of said valve member, spring coil and cup fitting said lower section of said wick.

References Cited UNITED STATES PATENTS 2,210,662 8/1940 Garvey 15-581 3,113,336 12/1963 Langnickel 15-581 X FOREIGN PATENTS 746,815 3/1956 Great Britain. 929,953 6/ 1963 Great Britain.

ROBERT W. MICHELL, Primary Examiner. 

